The subject matter discussed in the background section should not be assumed to be prior art merely as a result of its mention in the background section. Similarly, a problem mentioned in the background section or associated with the subject matter of the background section should not be assumed to have been previously recognized in the prior art. The subject matter in the background section merely represents different approaches, which in and of themselves may also correspond to embodiments of the claimed subject matter.
Within a computing environment, various data storage environments may be selected for persistently storing data. For example, data may be stored within file systems managed by an operating system that persistently stores file system data upon a hard drive, or data may be persistently stored within a database. Various types of databases are available, each having its own particular benefits and drawbacks. For example, so called relational databases provide the ability to “relate” various data tables to each other within the database, using common characteristics shared by each table. For example, in a relational database, an employee identifier may be used as a common characteristic to relate more than one table. Such a database structure has certain drawbacks, however, one of which is that the relationships necessitate a high level of computational overhead costs and computational complexity which limits the extent to which a relational database can be scaled.
Non-relational database models and implementations also exist and commonly exhibit better scalability, but also exhibit different drawbacks that are not associated with relational database models and implementations. For example, non-relational database implementations often exhibit improved scalability for storing large files or objects, but may be less suitable in other regards such as sorting selective datasets or implementing data guarantees for fast changing datasets.
Unfortunately, database queries that simultaneously reference information from multiple data stores are highly inefficient and detract from benefits that may otherwise be derived from the implementation of multiple data stores. Moreover, database queries that simultaneously reference distinct implementations of diverse database models may be wholly impracticable using previous database query mechanisms.